From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-2.8 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD,T_DKIM_INVALID shortcircuit=no autolearn=no autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 539531FC44 for ; Mon, 13 Feb 2017 19:51:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752420AbdBMTvT (ORCPT ); Mon, 13 Feb 2017 14:51:19 -0500 Received: from mail-ot0-f194.google.com ([74.125.82.194]:36763 "EHLO mail-ot0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751476AbdBMTvS (ORCPT ); Mon, 13 Feb 2017 14:51:18 -0500 Received: by mail-ot0-f194.google.com with SMTP id 36so13264819otx.3 for ; Mon, 13 Feb 2017 11:51:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version; bh=mV8PKVjzipPsYh8K00KUqFqkb9XHRnQ5aqFhJOS4SfM=; b=VdyqfB3fMUI2EjCO6lW++72Yz3w2JOyS1+hhR94UHQmPrsfF77vVlE21wC0n5LI9Ka 9OJHOs3DYWAuH+E/TEAvyLn5dOWjz4auHAasgAR2njvuKl8RMJOyAoBSFC+EAsaythM4 cyUNFAfebQmZXA9SW4QBmJ6yEcWsVljxikLz6iTd4z6SOk/zH7Yp+hCeqvL4pfKxXzHk Gz6XaPm4Y04tk93bNYLvLJXw2P9qEXwmLTf638fmVpf74lXIR0fz3Th8hsTmcZ2KJ61Q P9OnDQRF1Om++ECPZcKyAr9MqGSOqDdJsWWVlejfNrxPV2mgl0KUe0lkZbbGBWNAe4tZ Zyfg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:references:date :in-reply-to:message-id:user-agent:mime-version; bh=mV8PKVjzipPsYh8K00KUqFqkb9XHRnQ5aqFhJOS4SfM=; b=gBN+oXkmLqiuSJGlFTqwML8mazsihWlouBZznxPKFc9DXjVOGMZ2a6YgvhqCTjICcd G+L8g+cQ+DQrAuHOU3GGHXmvw/r0uA6YdykfYYW4QbR9QMR+tvxWEAxDnVVGecc1yAm7 V3HXJ5M1RMebm3i8itS4s3c2c/vv9AswSVy6OurPNKQpLxaWCxvhfvJMr26o69nDAl7b Yw98UOEfkMPhwlukiEIRviWfYpQd74LzX+IIv8isc2sTjLn5RXbcr26Ndw0HEA0LEh2B CvAyvoMYxiS8/e8uXDBmfOLyDzmxF7CJ3BrATnRM8/X0/pdC9QIJve8sP5NYIhMk5Eh2 NCMw== X-Gm-Message-State: AMke39mgu13bivpIy8fOBp7S8gTfkMM3jgJckP9ot+kvl2YcMxl9UDKlVicok82nrsir3g== X-Received: by 10.98.90.196 with SMTP id o187mr27609894pfb.30.1487015477368; Mon, 13 Feb 2017 11:51:17 -0800 (PST) Received: from localhost ([2620:0:1000:8622:d0e0:42a7:601f:5154]) by smtp.gmail.com with ESMTPSA id o125sm16195291pfb.109.2017.02.13.11.51.16 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Mon, 13 Feb 2017 11:51:16 -0800 (PST) From: Junio C Hamano To: Matthieu Moy Cc: Siddharth Kannan , git@vger.kernel.org, pranit.bauva@gmail.com, peff@peff.net, pclouds@gmail.com, sandals@crustytoothpaste.ath.cx Subject: Re: [PATCH 2/2 v3] sha1_name: teach get_sha1_1 "-" shorthand for "@{-1}" References: <1486752926-12020-1-git-send-email-kannan.siddharth12@gmail.com> <1486752926-12020-2-git-send-email-kannan.siddharth12@gmail.com> <1486752926-12020-3-git-send-email-kannan.siddharth12@gmail.com> Date: Mon, 13 Feb 2017 11:51:16 -0800 In-Reply-To: (Matthieu Moy's message of "Sun, 12 Feb 2017 10:48:56 +0100") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1.91 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Matthieu Moy writes: > Siddharth Kannan writes: > >> + if (!strcmp(name, "-")) { >> + name = "@{-1}"; >> + len = 5; >> + } > > One drawback of this approach is that further error messages will be > given from the "@{-1}" string that the user never typed. Right. > There are at least: > > $ git grep -n -A1 'strcmp.*"-"' | grep -B 1 '@\{1\}' > builtin/checkout.c:975: if (!strcmp(arg, "-")) > builtin/checkout.c-976- arg = "@{-1}"; I didn't check the surrounding context to be sure, but I think this "- to @{-1}" conversion cannot be delegated down to revision parsing that eventually wants to return a 40-hex as the result. We do want a branch _name_ sometimes when we say "@{-1}"; "checkout master" (i.e. checkout by name) and "checkout master^0" (i.e. the same commit object, but not by name) do different things. > builtin/merge.c:1231: } else if (argc == 1 && !strcmp(argv[0], "-")) { > builtin/merge.c-1232- argv[0] = "@{-1}"; > -- > builtin/revert.c:158: if (!strcmp(argv[1], "-")) > builtin/revert.c-159- argv[1] = "@{-1}"; These should be safe to delegate down. > builtin/worktree.c:344: if (!strcmp(branch, "-")) > builtin/worktree.c-345- branch = "@{-1}"; I do not know about this one, but it smells like a branch name that wants to be used before it gets turned into 40-hex.